How soon after tagging does a release actually get pushed to the website and to the deb repo?

Depends. Seems to be ~2/3 weeks on average between full releases (not counting pre-releases)

If we can deploy to Facebook infra and there are no outstanding deployment issues, we push to the repos.

ok... just asking, as 2.8.1 fixes a really annoying bug with Kinesis Firehose, so just a matter of figuring out if I should just wait for the push to the deb repos or try to pull it in manually

We should have a new release out to the repos tomorrow 🙂